URGENT!! Bacteria tend to grow exponentially, by a common factor over equal time intervals, because each cell divides into two daughter cells. A
particular bacteria culture begins with 1000 bacteria. The number of
bacteria doubles about every 12 h.

The first one, i believe, would be correct. all the others have one thing in common, and that's that they have repeating numbers. in the second one, x and y have repeating 6's and 3's, and in the third, x and y have repeating 6's as well. in the last one, there are repeating 3's. the first one has no repeating numbers.

I'm not sure but i think it's 1670km/h